I would like to make some comments here. The Portuguese reached Japan in the decade of 1540, and even if the contacts in Macau (China) were previous the permanent settlement was in the 1550 decade. Let us note that the British established near, in Hong-Kong, not shortly afterwards as stated but three centuries later.
The relations between Portugal and Japan can be consider intense in the beginning, even more after 1581 when the Portuguese Crown had the same ruler as the Castilian one that was established in the Philippines.
The Portuguese first Empire, in the Orient, was never an empire with large territorial masses, it was mainly an empire of trade, control of sea routes and strategic points, that we can consider a Thalassocracy. Portugal had never the resources or the ambition to conquest large land masses in Asia.
So, the objective was never of pure conquest, but essentially of trade and conversion to the Christianism. The contacts were mainly made throw Nagasaki. There was an annual ship between Macau and Nagasaki. The Spanish were the ones that followed and even if Portugal and Spain had the same king at the time there was quite a competition between Manila (that reported to “Mexico”) and Macau (that reported to Goa). The basics can be found in Wikipedia, the article has the essential without major errors: https://en.wikipedia.org/wiki/Japan%...ugal_relations
The Portuguese ships were known as the Black ships because the wood after so much time in the see was very dark.
The art of this period is quite interesting and it is known as Namban Art: https://www.google.pt/search?q=namba...UIBigB&dpr=1.1